Madsen Road Upgrade Works

Geoinventions Consulting Services Pty Ltd (GCS) was engaged by Fraser Coast Regional Council to provide a geotechnical design for the proposed Stone®Strong reinforced soil wall (RSW) required for the Madsen road upgrade project. This project involves the reconstruction of a 600m section of Madsen Road, Urraween from Morgan Circuit to south of Windsor Way to realign the existing road and allow for safer passage for motorists. Due to the height of the existing embankment and subsoil conditions, the project was deemed as a moderate risk to instability which GCS successfully addressed during the detailed design and construction phases of the wall.

The Stone® Strong system adopted for the build comprises of large precast interlocking concrete blocks. There are two standard block sizes, 24SF and 6SF. The 24SF block is 2.44m x 1.10m x 0.92m with a face area of 2.25m2 was predominantly used for this project. The large block size and engineered webbed design allows for rapid installation. Stone Strong blocks was selected for this project for both their structural properties and aesthetic appeal.

The Stone® Strong RSW is approximately 125.0m in length and has a maximum wall height of 10.58m with a service life of 120 years. At the highest part of the wall, the foundation material beneath the footprint of the structure had to be removed and replaced with crushed rock due to the presence of soft incompetent soil. A 150mm concrete footing was cast over the crushed rock layer to provide a level foundation for the Stone® Strong blocks.

GCS completed the Stone® Strong retaining wall design on schedule and assisted both the principal contractor SGQ and Fraser Coast Regional Council during the construction phase to deliver the retaining wall as per the design. The entire project was delivered on time and within the project budget.

Services Geoinventions provided include:

Provision of RSW design for the proposed retaining wall.

Verification of foundation material.

Regular site inspections to ensure the construction is in accordance with design requirements.